Vanguard International Semiconductor Corporation

Cadence Design Systems, Inc.

Pmc-sierra, Inc.

Jeffrey Scott Earl

Luigi Ternullo, Jr

Michael C Stephens, Jr

Sandeep Brahmadathan

Christopher Ematrudo

John Michael MacLaren

George Apostol, Jr

Anne Hughes

Takashi Ueda

Todd Barth

Michael F Vincent

Utpal Mahanta

Douglas A Cross

Various embodiments described herein provide for a data transfer mechanism for a memory device, such as a Double Data Rate (DDR) memory device, which can improve critical timing within the memory device without a latency impact. In addition, various embodiments described herein provide for a switching sequence for a memory device, which can improve switching time for the memory device.

Memory data transfer and switching sequence

A delay line can include a number of delay elements connected in series, each selected to impart an overall delay to an input signal. The delay line can include delay selection logic to select a subset of the delay elements to delay the input signal. The delay line can include delay element enable logic to enable the selected subset of the delay elements to delay the input signal. Further, the remaining delay elements can be disabled from contributing any delay to the input signal, and a respective periodic signal can be provided to at least one of the remaining delay elements to cause the at least one remaining delay elements to output an output signal that is a function of the respective periodic signal and that has a frequency less than that of the input signal. This configuration can reduce asymmetric aging effects on the delay line.

Circuits and methods for reducing asymmetric aging effects of devices

Various embodiments provide for a multi-channel memory interface capable of supporting a multi-channel memory module (e.g., DIMM) that combines different memory types, such as DDR4/DDR5, DDR5/LPDDR5, or LPDDR4/LPDDR5, through a single physical layer (PHY) interface.

Multi-channel memory interface

A system and method providing timing alignment of a data mask (DM) signal with respect to a data strobe (DQS) signal for memory devices not designed for adjusting such alignment is provided. Alignment between data signals (DQ) and a DQS signal is first achieved during a first write training procedure where a data delay value is optimized for one of the DQS or DQ signals. Subsequently, using the optimum delay value from the first write training procedure, a second write training procedure is initiated. In the second write training procedure, timing alignment between the DM signal and the DQ signals is achieved by determining an optimal delay value of the DM signal relative to the DQS signal.

System and method for data-mask training in non-provisioned random access memory

A chip select signal is trained where the chip select signal is delayed to centrally align its pulses with a positive edge of a memory device's clock cycle. Over repeated iterations, the memory device stops its clock for an interval and a delayed pulse of the chip select signal is generated. The pulse delay is incrementally changed with each iteration. When the delay results in the trailing edge of the delayed pulse aligning with the positive edge of the last cycle before the stoppage interval, the memory device captures the contents of a computer bus, thus detecting a trailing edge delay value. When the delay results in the leading edge of the delayed pulse aligning with the positive edge of the last cycle, the device no longer captures the contents, thus detecting a leading edge delay value. A value between these values is then set as the optimal delay.

Method of aligning timing of a chip select signal with a cycle of a memory device

A method and system in accordance with the present invention provides for a method and circuit for oversampling using a delay element in which input clock signals and input data signals are affected by phase and time delays to provide for the circuit generating samples providing a greater granularity of detail over a period, thereby reducing error probabilities.

Multiple samples with delay in oversampling in phase

In a bus interface unit, a first communications interface is provided for the coupling of a first plurality of peripheral devices of different device types to facilitate communication with a selected one of the first plurality of peripheral devices of different device types. In addition, a second communications interface is provided for coupling to a first bus of an integrated circuit (IC) to facilitate communication with a selected one of a second plurality of devices of the IC, via the first bus. A controller is provided for the coupling of the first and second communications interfaces to facilitate communications between selected ones of the first and second plurality of devices, dynamically selecting and employing a communication protocol consistent with the device type of the selected one of the first plurality of peripheral devices. The bus interface unit has particular application to interfacing external devices with the core of an SOC.

Flexible data transfer to and from external device of system-on-chip

A new method of detecting a reticle option layer in an integrated circuit device has been achieved. The method may be applied to detect the presence of the threshold voltage implantation reticle option layer by direct die probing or by probing a pin of a package integrated circuit. The current through a first MOS transistor is measured by forcing a test voltage on the drain and the gate. The gate and the drain of the first MOS transistor are connected together while the source is connected to a reference voltage. The first MOS transistor has the standard threshold implantation but not the threshold voltage reticle option. The current through a second MOS transistor is measured by forcing the same test voltage on the drain and the gate. The gate and said drain of the second MOS transistor are connected together while the source is connected to a reference voltage. The second MOS transistor has the standard threshold voltage implantation and the threshold voltage implantation reticle option layer. The current through the first NMOS transistor and the current through the second MOS transistor are compared to detect the presence of the threshold voltage implantation reticle option layer in the integrated circuit device.

Reticle option layer detection method

Described is a method for verification of proper address generation in packet based memory protocol (Direct RDRAM) devices during the auto-refresh or self-refresh cycle that does not require changes to the interface logic or core signal generation. The method requires minimal additional logic while using the core control signals that function similarly to the RAS, CAS, and WE signals in a standard DRAM. Initially, high level (,) data are written to all of the memory cells of one bit line. The signals are manipulated, and a refresh is performed. As each memory cell is addressed during the refresh, the data are changed to a low level (,). Addressing is then verified by observing the data stored in the memory cells and confirming that a low level (,) is now stored. The method may be extended to standard DRAM devices.

Test mode for verification of on-chip generated row addresses

A circuit for a DRAM is described which, when in test mode, notifies a tester when the self-refresh operation of a dynamic random access memory (DRAM) reaches various stages of completion. By signaling the tester when, i.e., &frac18;, &frac14;, &frac12;, etc. of the self-refresh cycle is reached, the amount of time needed for verification of the self-refresh oscillator frequency is reduced correspondingly by a factor of 8, 4, 2 etc. The signaling of a partial test time is achieved by adding self-refresh status logic circuits which decode the high order most significant bits of the refresh address counter. The activation of the third most significant bit signals completion of &frac18;th of the self-refresh cycle, the activation of the second most significant bit signals completion of &frac14;th of the self-refresh cycle, the activation of the most significant bit signals completion of &frac12; of the self-refresh cycle, and deactivation of the most significant bit signals completion of the self-refresh cycle.

Self-refresh test time reduction scheme

The present invention provides an input receiver in a differential amplifier or modified differential amplifier configuration which adjusts the input high and low voltage signals compatible with multiple input/output (I/O) interfaces, including transistor-transistor logic (TTL), Low Voltage TTL (LVTTL), and Stub Series Terminated Logic (SSTL) interfaces. Transistors in a differential amplifier or modified differential amplifier configuration that receive a reference.sub.-- voltage signal and receiver.sub.-- enable signal are adjusted in accordance to the input high signal and input low signal requirements for a selected type of interface, while other transistors remain at a relatively constant voltage. Once a particular type of interface has been selected, the gate voltages for the transistors that receive the reference.sub.-- voltage and receiver.sub.-- enable signals remain relatively constant. The switching speed of an input receiver is not adversely affected by the additional load of non-operational FETs for one or more of the I/O interface types due to the supply of constant gate voltages to the transistors.

Multiple input/output level interface input receiver

A regulator system for an on-chip-generated supply voltage includes a voltage detection circuit, a power-up mode detection circuit, a normal mode detection path, and a power-up detection path. The voltage detection circuit monitors the on-chip-generated supply voltage and generates a signal that indicates the level of this supply voltage. The power-up mode detection circuit detects when the chip is in the power-up mode and generates a path select signal. The path select signal causes the regulator system to select the power-up detection path during the power-up mode and to select the normal detection path when not in the power-up mode. The power-up detection path includes voltage regulation circuitry that does not rely on a reference voltage. In one embodiment, the power-up detection path includes a logic gate coupled to receive the signal from the voltage detector. The logic gate is skewed to have a trip point that corresponds to voltage level slightly greater than that of the external supply voltage. The logic gate controls the on-chip voltage generator to maintain the on-chip-generated voltage level at a magnitude greater than that of the external supply voltage. During power-up, the power-up detection circuit selects the power-up detection path, thereby avoiding the need to disable the on-chip voltage generator as in conventional systems that depend on a reference voltage.

On-chip-generated supply voltage regulator with power-up mode

The present invention provides an input receiver that slows the signal fluctuation by limiting the amount of electrical currents flowing through the input receiver. The limiting of electrical current flowing through the input receiver slows the input signal of the receiver which in effect filters out some level of glitches of an input signal. In one embodiment, the input receiver is constructed and implemented in a structure similar to a differential amplifier for a single interface. In another embodiment, the input receiver is constructed and implemented in a modified differential amplifier for a single interface. In a further embodiment, the input receiver is constructed and implemented in a modified differential amplifier for multiple interfaces.

Input receiver for limiting current during reliability screening

A circuit for disabling a two-phase charge pump includes a pump select circuit and a disable control circuit. The pump select circuit is configured to select one control signal from a plurality of control signals in response to at least one select signal. The selected signal is in effect provided to the disable control circuit, which also receives a pump disable signal. A voltage sensing circuit asserts the pump disable signal when the pumped voltage reaches a predetermined maximum level. While the pump disable signal is de-asserted, the disable control circuit in effect provides the selected signal to the two-phase charge pump as a pump control signal. However, when the pump disable signal is asserted, the disable control signal latches the current logic level of the pump control signal so that the pump control signal does not transition while the pump disable signal is asserted. As a result, the two-phase charge pump is prevented from performing an extra pump cycle that would cause the pumped voltage to exceed the predetermined maximum level.

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San Jose, CA, United States of America

Jeffrey Scott Earl